First of all, this is wonderful that a good ol' semi-Mexican such as I and an Aussie can communicate across the Pacific with perfect ease. God bless lingua francas!
Now that I have that out of my system, here's what I suggest. It shows both sensitivity to your audience and the requisite humility. (Something that machine translators probably will not have anytime soon.)
Make a version of each page that you want foreign-language-available with a tag at the top such as lang="xx"
(in place of the present "lang="en"" that you have now), then have a nicely translated phrase in the target language stating: "We regret that this page is only available in English or with a poor quality automatic translation." Then give a link choice. "English: http...... Xx: http....." Don't make your disclaimer any more complicated than this - it might not translate at all well.
This way, your organi(z/s)ation will not look ignorant nor insensitive, just strapped for cash or help.